Loading multiple assetbundles from server

I've been trying to setup a AssetBundle Loader system for our project, but the documentation about this is confusing and I'm still not sure how or if I can setup the system the way I want to.

I want to store several prefabs in one AssetBundle each. So, AssetBundle X stores Prefab X.

I was able to get this to work in a simple sample script:

Code (CSharp):

1. public class Loader : MonoBehaviour
2. {
3.     private AssetBundleCreateRequest bundleRequest;
4.     private UnityWebRequest request;
5.     private bool loaded;
6.  
7.     private void Start()
8.     {
9.         request = UnityWebRequest.GetAssetBundle(AppConfig.ASSETBUNDLE_URL + "myBundle/1");
10.         request.SendWebRequest();
11.     }
12.  
13.     private void Update()
14.     {
15.         if (!request.isDone || loaded){
16.             return;
17.         }
18.         var bundle = DownloadHandlerAssetBundle.GetContent(request);
19.         var myGameObject = Instantiate(bundle.LoadAsset("MyPrefab")) as GameObject;
20.         loaded = true;
21.  
22.     }
23. }

However it worked only for one bundle and only If I specify the name of the prefab, in that scene. I wanted to load all the assetsBundles in a "loading" scene to then instantiate the prefabs in the next scene.

TLDR:
- How do I save assetbundles for later use in the app

 

I'm doing pretty much the same thing in my project.

The official tool from unity will do exactly what you're after.
https://assetstore.unity.com/packages/tools/utilities/asset-bundle-browser-93571

And following the Manual for works like a charm.
https://docs.unity3d.com/Manual/AssetBundles-Browser.html

 

Since I posted this I finally understood what I was doing wrong. To make Unity cache asset bundles GetAssetBundle HAS TO have the version otherwise it will not cache it.

However, now I'm having a different issue related to the bundles. I created a coroutine to load one asset bundle and works fine. Then I called this coroutine for each bundlename in a list. When I do this only the first bundle works, when it tries to load the second one it keeps getting the reference to the first one.

Code (CSharp):

1. private IEnumerator GetAssetBundleFromRemote(string bundleName)
2.     {
3.         var bundleUrl = Path.Combine(RemotePath, bundleName);
4.         var webReq = UnityWebRequest.GetAssetBundle(bundleUrl, 1, 0);
5.         var handler = webReq.downloadHandler as DownloadHandlerAssetBundle;
6.         yield return webReq.Send();
7.  
8.         if (webReq.responseCode == 0){
9.             Debug.Log(bundleName + "__>" + "Loading from cache");
10.         }else if (webReq.responseCode == 200){
11.             Debug.Log(bundleName + "__>" + "Loading from server");
12.         }
13.  
14.         Debug.Log(bundleName + "__>" + "Analizing response");
15.         var bundle = handler.assetBundle;
16.        
17.         if (bundle == null){
18.             Debug.Log(bundleName + "__>" + "No Bundle Found");
19.             yield break;
20.         }
21.        
22.         Debug.Log(bundleName + "__>" + "Bundle Found");
23.         Debug.Log(bundleName + "__>" + "Bundle Name: " + bundle.name);
24.         foreach (var assetName in bundle.GetAllAssetNames()){
25.             Debug.Log("Asset: " + assetName);
26.         }
27.         var prefab = bundle.LoadAsset<GameObject>(bundleName);
28.  
29.         if (prefab != null){
30.             Debug.Log(bundleName + "__>" + "Prefab Found");
31.             Instantiate(prefab, transform, false);
32.  
33.         }
34.         bundle.Unload(false);
35.        
36.         yield return new WaitForSeconds(3);
37.     }

When it tries to load the second bundle this code:

Code (CSharp):

1. foreach (var assetName in bundle.GetAllAssetNames()){
2.             Debug.Log("Asset: " + assetName);
3.         }

Gives me the assets of the first bundle.

This bundles don't have anything in common

 

having same issue

 

i am using WWW for downloading assetbundle from google drive. not unitywebrequest . WWW is working fine for 1 asset bundle with size less then 100mb , but when it exceeds 100mb its giving downloading error. but when i divide 1 into 2 asset bundle to reduce size problem it download both but show error if i try to get 2nd asset bundle.

Code (CSharp):

1. void Awake()
2.     {
3.         if (Application.isEditor && removeCache)
4.             Caching.ClearCache();
5.  
6.         StartCoroutine(GetAssetBundle());
7.     }
8.    
9.     IEnumerator GetAssetBundle()
10.     {
11.         www = new WWW[url.Length];
12.         for (indexOfDownloadableFiles=0; indexOfDownloadableFiles < url.Length; indexOfDownloadableFiles++)
13.         {
14.              Debug.Log("Dowloading Started");
15.  
16.            
17.             www[indexOfDownloadableFiles] = WWW.LoadFromCacheOrDownload(url[indexOfDownloadableFiles], version );
18.            
19.             yield return www[indexOfDownloadableFiles];
20.  
21.             if (www[indexOfDownloadableFiles].error != null)
22.             {
23.                 //if error in downloading asset bundle show error popup
24.                 if (errorDownloadDb)
25.                     errorDownloadDb.SetActive(true);
26.                 yield break;
27.  
28.                 throw new Exception("WWW download had an error: " + www[indexOfDownloadableFiles].error);
29.             }
30.            
31.          
32.  
33.        
34.             AssetBundle assetBundle; assetBundle = www[indexOfDownloadableFiles].assetBundle;
35.      
36.             if (!assetBundle && errorDownloadDb)
37.             {
38.                 errorDownloadDb.SetActive(true);
39.                 yield break;
40.             }
41.  
42.             if (canLoadScene)
43.             {
44.                 LoadSceneMethod(assetBundle);
45.             }
46.             else
47.             {
48.  
49.                 if (prefabsName.Length > 0)
50.                 {
51.                    
52.                     //instantiating prefabs
53.                     foreach (string prefabName in prefabsName)
54.                     {
55.                         Debug.Log("PrefebName" + prefabName);
56.                         AssetBundleRequest assetLoadRequest = assetBundle.LoadAssetAsync<GameObject>(prefabName);
57.                         GameObject AssetBundleObj = Instantiate(assetLoadRequest.asset) as GameObject;
58.                         AssetBundleObj.SetActive(true);
59.                         Debug.Log("AssetBundleObj: " + AssetBundleObj.name);
60.                     }
61.                 }
62.                 Debug.Log("BundleName: "+assetBundle.name);
63.                
64.                 assetBundle.Unload(false);
65.                 www[indexOfDownloadableFiles].Dispose();
66.  
67.                  Debug.Log( " Spawned");
68.  
69.             }
70.         }
71.             if (showContinue && continueButtonSplash)
72.             {
73.                 continueButtonSplash.SetActive(true);
74.             }
75.  
76.             if (loadingObjGameplay)
77.                 loadingObjGameplay.SetActive(false);
78.            
79.        
80.     }
81.  
82.    

 

That's the error that i'm getting...

 

I was stuck in the same problem,
seems that you have to give a different name to the cached assetbundle, through the CachedAssetBundle structure

Code (CSharp):

1.  
2. ...
3. CachedAssetBundle cachedAssetBundle = new CachedAssetBundle();
4.         cachedAssetBundle.name = uniqueName;
5. ...
6. UnityWebRequest uwr = UnityWebRequestAssetBundle.GetAssetBundle(mUri, cachedAssetBundle, 0);
7. ...
8.  

because internally, seems that filenames are identical (filename is used as key along the hash number)